The Knowledge Base

The knowledge base is a storehouse of facts, rules, and heuristics that relate to the domain in which the system provides advice. As far as possible, it contains everything that might be useful to the ES in solving problems. 

Even though the two knowledge bases may overlap to a great extent, this conceptual distinction is very important, and the reason was touched upon at the end of Sec. B3.1, where we mentioned the work of John Warfield [8] and the idea of a problematique , an extended view of the service required that encompasses 

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Knowledge hose The knowledge base contains the encoded knowledge which is needed to solve a certain problem. The knowledge can be represented in the form of facts or rules. 

Knowledge acquisition subsystem The task of the knowledge acquisition subsystems is to assemble and upgrade the knowledge base. A major task is to verify the data and check for consistency. 

The most recent version of EROS has a clearcut separation of the system proper, which performs all the manipulations on chemical structures and reactions, from the knowledge base, which defines the scope of it.s application (Figure 10.3-7). 

The knowledge base is essentially two-fold on one hand it consists of a series of procedures for calculating all-important physicochemical effects such as heats of reaction, bond dissociation energies, charge distribution, inductive, resonance, and polarizability effects (.see Section 7.1). The other part of the knowledge base defines the reaction types on which the EROS system can work. 

M J1990. Calculation of Conformational Ensembles from Potentials of Mean Force. An Approach o the Knowledge-Based Prediction of Local Structures in Globular Proteins. Journal of Molecular Siology 213 859-883. 

Computer-aided process synthesis systems do not mean completely automated design systems (57). Process synthesis should be carried out by interactive systems, in which the engineer s role is to carry out synthesis and the machine s role is to analy2e the performance of synthesized systems. Computet apphcations in the future will probably deal with the knowledge-based system in appHed artificial intelligence. Consequendy, research on computer-aided process synthesis should be directed toward the realization of such systems with the collaboration of experienced process engineers. 

Of these, the first two place demands on the processing speed of the knowledge-based system and its integration with the environment, eg, data acquisition interfaces. The third impacts on the nature of the computational cycle and the system s abiHty to reschedule its own computations. The latter two place demands on the representation and reasoning capabiHties of the system, and are the most interesting from a knowledge-based system viewpoint. 

MI Sippl. Calculation of conformational ensembles from potentials of mean force. An approach to the knowledge-based prediction of local structures m globular proteins. I Mol Biol 213 859-883, 1990. 

As discussed in Chapter 2, most of the basic resources you will need are fairiy self-evident time of staff will almost certainly be the latgest single cost. Support expenses and travel also require funding. In addition, in the course of yourwork to date you may have identified specific resource requirements, such as computer software for hazard analysis or project management, or consulting services that fill in specific gaps in the knowledge base. 

If the nature of the problem is not readily apparent, then it might be necessary to go to the rule-based level. In this case a diagnostic rule will be applied to identify the state of the plant and an action rule used to select an appropriate response. Control will revert to the skill-based level to actually execute the required actions. More abstract functions such as situation evaluation and planning will only be required at the knowledge-based level if the problem cannot not be resolved at the rule-based level. 

Detailed procedures will only be required in unusual situations where the usual rules of thumb do not apply and the worker is likely to be in the knowledge-based mode. In Chapter 4, and case study 3 in Chapter 7, a systematic framework for developing procedures, in which their format and content is based on a detailed analysis of the tasks to be performed and the normal skill level of the person who will perform the tasks, will be described. 

The term process control is often used when machine control is actually performed. As the knowledge base of the fundamentals of the molding process continues to grow,... 

With this database in hand, a simple question is asked [29] How different is a knowledge-based potential derived from this lattice database compared to the actual energy function used to construct the database If statistical errors are negligible and the knowledge-based method is perfect, the answer is expected to be They are exactly the same. ... 

The central hypothesis of the knowledge-based approach [16, 17] is that pairwise contacts follow an exponential Boltzmann-like distribution [33] according to its interaction energy... 

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